We consider an inertial active Brownian particle of mass \(m\)  is diffusing in a 2D suspension fluid confined in a circular cavity. The active particle can exit through the openings as depicted in Fig. 1. We model unconstrained dynamics of the active particle by the following set of equations [1]}, [2]}, [3]}:
\(m\ddot{x} &=& -\gamma \dot{x} + F_0 \cos {\theta }+\xi _x(t); \\m\ddot{y} &=& -\gamma \dot{y}+F_0 \sin {\theta } + \xi _y(t); \\\dot{\theta } &=& \xi _\theta (t). \) 
